If you are going to make chips, cut them into 6 triangles before letting them dry.
There a couple options:
Fry: Add enough corn, safflower or vegetable oil to a skillet to have about 1/2" and place over medium heat for about 4 to 6 minutes. Once the oil is hot but not smoking, fry each tortilla for about 45 seconds to 1 minute per side until it achieves a nice golden tanned color (not overwhelmingly brown or it will taste bitter) and crisp texture. To drain, place vertically on a tall metal strainer or lay flat on paper towels.
Toast or Bake: Either let the tortillas toast over a hot comal or dry skillet over medium heat, turning occasionally until they toast and crisp; or place them on a baking sheet in a 350 degree oven for about 25 to 30 minutes, turning them once halfway through, until tanned and crisp.
Different from tostadas, chips typically have a nice sprinkling of kosher or sea salt.
Once you cut the tortillas into triangles and let them dry, you have a couple options as well. They do taste very different, so try and see which method you like best:
Fry: Add enough corn, safflower or vegetable oil to a skillet to have about 1/2 inch and place over medium high heat for about 4 to 6 minutes. Once the oil is hot but not smoking, add enough tortilla triangles (depending on how large your skillet is) to have them in a single layer. It doesn't matter if some triangles get cozy with others, but you don't want to add so many that there is more than a cozy single layer.
Let them fry for about 45 seconds to 1 minute on one side, before flipping them over. Let them fry and crisp on the other side for another 30 seconds to 1 minute or until they have achieved a nice golden tanned color (but not overly browned) and are crispy. Remove them from oil and place them in a baking sheet covered with paper towels. Some cooks like to drain them in large and tall metal colanders. Sprinkle with salt to taste.
Toast or Bake: Spray or brush a very light coat of vegetable or corn oil on the tortilla triangles. Either toast over a hot comal or dry skillet over medium heat, turning occasionally until they toast and crisp anywhere from 10 to 15 minutes, flipping every once in a while; or place them on a baking sheet in a 350 degree oven for about 25 to 30 minutes, turning them once or twice along the way, or until tanned and crisp. Remove from oven, sprinkle with salt and let them cool.